The results suggested that PEPD, SLC15A1, and SLC5A3 were candidates for individual lethal genes specific to lung cancer, and pairs of CBS-SLC7A11, CBS-SLC3A2, CMPK1-PTDSS1, CMPK1-PLD2 were candidate synergistic lethal genes specific in the tumors. This evidence concerns the gene PEPD and lung cancer.